Body stages Stage 5 of 11

24–36 h

Glycogen largely spent

Most of the liver's stored sugar has been used. The body now makes almost all its glucose fresh, mainly from fat-derived glycerol and amino acids.

Measured in humans, HighFree

What studies measured

Gluconeogenesis supplies 82% of glucose; liver glycogen near exhausted.

How it may feel

Hunger is often quieter than on day one.

What to do

Two to three litres of fluid a day to thirst, with sodium. Sleep early.

Sources

  1. Rothman 1991Quantitation of hepatic glycogenolysis and gluconeogenesis in fasting humans with 13C NMR. Science, 1991.
  2. Nilsson and Hultman 1973Liver glycogen in man--the effect of total starvation or a carbohydrate-poor diet followed by carbohydrate refeeding. Scand J Clin Lab Invest, 1973.
  3. Owen 1998Protein, fat, and carbohydrate requirements during starvation: anaplerosis and cataplerosis. Am J Clin Nutr, 1998.

What studies measured in healthy adults, not a reading of your own body. Stop and seek help if you feel unwell; the signs to stop for are listed under Stop signs on the safety page.

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